This was mentioned in the book "eco-science" written by obamas science czar John Holdren. He talks about putting particulates into the air to block out the sun.

Other things in the book: forced abortions, babies taken from their mothers, mass sterilization of humans though drugs in the water supply, a "Planetary Regime", government dictating family size, surrendering national sovereignty etc...

Same shit the World Federalists all shill for.